Electromagnetic contactors having various configurations have been known heretofore. For example, K. A. Grunert et al. Pat. No. 3,727,157, dated April 10, 1973, shows an electromagnetic contactor wherein the magnet frame is used as a mounting bracket and is arranged to be connected by a pair of screws to a mounting panel. A pair of wire clips having spaced portions engagable with the housing and the mounting bracket are used for readily detachably mounting the housing on the bracket and for readily detaching the housing from the bracket for enabling easy access to the interior of the assembly without removing the bracket (magnet frame) from the mounting panel. Also, A. Brovedan Pat. No. 3,469,215, dated Sept. 23, 1969, and E. H. Kuhn Pat. No. 4,087,770, dated May 2, 1978, show electromagnetic relays having a pair of cushions or elastomer pads between the magnet frame and the housing and between the magnet frame and the coil to absorb any shocks imposed on the magnet frame when the armature is actuated. A separate spring clip presses the coil against the magnet frame and the magnet frame against the base of the housing in the Brovedan patent. In the Kuhn et al patent the upper housing part is attached to the lower housing part by four screws and presses down on the encapsulated coil so as to compress slightly the rubber cushions and retain the coil and the magnet yoke within the magnet housing. While these prior contactors and relays have been useful for their intended purposes, they have nevertheless been handicapped by certain disadvantages such as difficulty of assembly and disassembly, parts being subject to undesired movement under shock and vibration if held together by readily detachable means, and difficulty of mounting accessory devices such as mechanical and electrical interlocks, auxiliary contacts and switches. This invention relates to improvements thereover.